Sad.. my relationship is falling apart.

I fewl everytime we argue things get worse, words get twisted and i just cant deal with it. A little example like currently happening now. My SO went out drinking last night got really drunk and he had to drop off hia friend. His phone died and took him about an hour and a half i got upset because i was worried sick as i had no other means to check on his well being. He got mad because i got upset even tho i didnt yelled at him anyways today i have a dr appointment for my prenatal care and he was too hung over to bring me so i took a cab. Granted im still upset because i told him about it before him going out so i kinda had a little vent on fb i know (immature) but it was in the heat of the moment and i deleted it. Somehow he found out about it after hours later and hell broke loose, yes karma for me doing it. Then the argument turnefs into throwing shit in the face and recalling everything bad done in the past. I just dont even know what to do and u know he wont hesitate to break uo with a 13 wk pregnant fiance.